Medium severity · published Sep 2, 2026
CVE-2026-84655
Jenkins 2.579 and earlier, LTS 2.568.2 and earlier does not escape map keys when serializing objects as JSON and Python through its REST API, allowing attackers able to control…
4.3
CVSS
0.3%
EPSS
No
On KEV
Description
Jenkins 2.579 and earlier, LTS 2.568.2 and earlier does not escape map keys when serializing objects as JSON and Python through its REST API, allowing attackers able to control map property names to inject arbitrary fields into JSON and Python API responses.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
None
Integrity
Low
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 24% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
JE
Jenkins · Jenkins
through 2.568.2; through 2.579 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-84655
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-84655
Vendor Advisory
https://www.jenkins.io/security/advisory/2026-09-02/#SECURITY-3879
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